Proposition: Prop. 11.18: Plane through Straight Line Perpendicular to other Plane is Perpendicular to that Plane
(Proposition 18 from Book 11 of Euclid's “Elements”)
If a straight line is at right angles to some plane then all of the planes (passing) through it will also be at right angles to the same plane.
![fig18e](https://github.com/bookofproofs/bookofproofs.github.io/blob/main/_sources/_assets/images/euclid/Book11/fig18e.png?raw=true)
Modern Formulation
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Table of Contents
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References
Adapted from (subject to copyright, with kind permission)
- Fitzpatrick, Richard: Euclid's "Elements of Geometry"
Adapted from CC BY-SA 3.0 Sources:
- Prime.mover and others: "Pr∞fWiki", https://proofwiki.org/wiki/Main_Page, 2016